Particle Transformations in the "Regeneration Zone": The Biology and Chemistry of Mesopelagic Aggregates

“再生区”中的粒子转变：中层聚集体的生物学和化学

• 批准号: 9015602
• 负责人: Cynthia Pilskaln
• 金额: $ 10.14万
• 依托单位: Monterey Bay Aquarium Research Institute
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1991
• 资助国家: 美国
• 起止时间: 1991-02-01 至 1994-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9015602&HistoricalAwards=false
• 关键词: Particle; Transformations; Regeneration; Zone; Biology

Most organic matter synthesized in surface waters of the sea is returned to inorganic constituents within the upper 500 m, or "regeneration zone." Oceanographers attribute these chemical transformations mostly to living organisms. Yet surprisingly little is known about the biology of remineralization below the euphotic zone: whether the responsible organisms are dominantly metazoan or microbial and whether or not they occur on the larger particles that deliver material to depth. Dr. Pilskaln, together with Dr. Silver will conduct a 2-year study in Monterey Bay, and accessible, comparatively deep water site, to study the role of both microbes and zooplankton in the remineralization of particles 1mm. Using a combination of in situ observations and laboratory measurements, she will study both the abundant marine snow particles and very large aggregates (m size) that can serve as model systems for such studies. She plans to (1) measure the size and abundance of the aggregates, (2) determine their chemical properties and associated living communities, (3) measure regeneration-related activities of the communities on the particles, and (4) compare and particle-related remineralization rates to those measured by sediment traps in the area. For these measurements, she will use field surveys with a Romotely Operated Vehicle (ROV) and a Marine Snow Camera, a variety of sampling devices operated from the ROV, and a series of experiments on natural samples incubated on shipboard and in the laboratory. In year 2, Dr. Pilskaln transects the California Current to learn whether the very large aggregates, which are hypothesized to be regeneration centers to Monterey Bay, occur in significant numbers further offshore. These results will increase the understanding of the biology of midwater remineralization and the role that particles can play in the process.

海洋表层水中合成的大多数有机物在 500 m 的上部或“再生区”内返回到无机成分。 海洋学家将这些化学变化主要归因于生物体。 然而，令人惊讶的是，人们对真光带以下再矿化的生物学知之甚少：负责的生物体是否主要是后生动物或微生物，以及它们是否发生在将物质输送到深处的较大颗粒上。 Pilskaln 博士与 Silver 博士将在蒙特利湾这个交通便利、相对较深的水域进行为期 2 年的研究，以研究微生物和浮游动物在 1 毫米颗粒再矿化中的作用。 她将结合现场观测和实验室测量，研究丰富的海洋雪颗粒和非常大的聚集体（米大小），这些聚集体可以作为此类研究的模型系统。她计划（1）测量聚集体的大小和丰度，（2）确定它们的化学性质和相关的生活群落，（3）测量颗粒上群落的再生相关活动，以及（4）比较和颗粒-将再矿化率与该地区沉积物收集器测量的再矿化率联系起来。 对于这些测量，她将使用遥控潜水器 (ROV) 和海洋雪相机、由 ROV 操作的各种采样设备进行现场调查，并对在船上和实验室中培养的自然样本进行一系列实验。 第二年，Pilskaln 博士横断了加州洋流，以了解被假设为蒙特利湾再生中心的超大型聚集体是否大量出现在离岸较远的地方。 这些结果将增进对中层水再矿化生物学以及颗粒在该过程中发挥的作用的理解。